How to reduce elevated mercury levels in individuals with autism?

Management of Elevated Mercury Levels in Individuals with Autism

Chelation therapy with succimer (dimercaptosuccinic acid) is the recommended first-line treatment for reducing elevated mercury levels in individuals with autism. 1

Understanding Mercury and Autism

Mercury exposure has been proposed as a potential environmental factor that may contribute to autism spectrum disorders in susceptible individuals. The relationship between mercury and autism involves complex mechanisms:

• Mercury may act as a hapten (combining with endogenous proteins) and trigger autoimmune reactions in the brain 2
• These reactions can lead to the formation of brain autoantibodies (neuroantibodies) that may contribute to neurological symptoms 2
• Evidence suggests that brain autoantibody levels in autism correlate with both autism severity and blood mercury levels 2

Diagnostic Assessment

Before initiating treatment:

1. Confirm elevated mercury levels through appropriate testing:

   • Blood mercury levels (reflects recent exposure)
   • Hair analysis (reflects longer-term exposure)
   • Urine testing (after provocation with a chelating agent)

2. Determine mercury source and exposure route:

   • Environmental sources (air pollution) 3
   • Dietary sources (certain fish species) 3
   • Other potential sources (dental amalgams, certain medications)

Treatment Protocol

First-Line Treatment: Chelation Therapy

For confirmed elevated mercury levels:

• Succimer (DMSA) - FDA-approved oral chelating agent 1:
  • Dosage: Based on weight and severity of mercury elevation
  • Administration: Oral capsules or compounded liquid
  • Duration: Typically 19-day cycles with 2-week rest periods between cycles
  • Monitoring: Regular assessment of mercury levels, complete blood count, liver and kidney function

Dietary Modifications

• Eliminate high-mercury fish from diet 3:

  • Avoid: King mackerel, marlin, orange roughy, shark, swordfish, tilefish, bigeye tuna
  • Choose low-mercury fish options when consuming seafood:
    • "Best Choices": Salmon, anchovies, sardines, trout, tilapia, shrimp, catfish, crab, flounder
  • Limit fish consumption to FDA-recommended amounts based on mercury content

• Increase dietary omega-3 fatty acids from low-mercury sources 3:

  • Consider purified fish oil supplements tested for mercury content
  • Target 2 or more servings of low-mercury fish/seafood per week (8+ ounces total)

Supportive Measures

• Antioxidant support:

  • Vitamin C and E supplementation to combat oxidative stress
  • N-acetylcysteine (NAC) to support glutathione production

• Gut health optimization:

  • Probiotics to support healthy microbiome
  • Dietary fiber to support elimination

Monitoring and Follow-up

• Regular testing of mercury levels to assess treatment efficacy
• Monitor for potential side effects of chelation therapy:
  • Gastrointestinal symptoms
  • Skin rashes
  • Changes in kidney or liver function
  • Mineral depletion (zinc, copper, etc.)

Important Considerations and Caveats

1. Evidence quality: Research on mercury's role in autism shows mixed results 3. While some studies show correlations between mercury levels and autism severity 2, 4, others have found no mercury in the locus ceruleus neurons of individuals with autism 5.

2. Individual susceptibility: Genetic factors may influence susceptibility to mercury toxicity, including:

   • Sex differences (males may be more susceptible) 6
   • Polymorphisms in glutathione-related genes 6
   • Variations in detoxification pathways

3. Treatment risks: Chelation therapy carries potential risks and should be conducted under close medical supervision with appropriate monitoring.

4. Prevention strategies:

   • Minimize mercury exposure through dietary choices
   • Reduce environmental exposures when possible
   • Consider genetic testing for susceptibility factors

By following this structured approach to reducing elevated mercury levels, clinicians can address this potential contributing factor in individuals with autism while minimizing treatment risks.